The Biospecimen Repository Core is designed to provide support to the basic translational research efforts ofthe SPORE. The Core will play a central role in collecting, annotating, storing, distributing, and tracking prostate cancer tissue and blood biospecimens from patients enrolled in research protocols. Detailed biospecimen annotation, including documentation of preanalytic processing variables, pathology findings, and patient clinical history information will be recorded in robust relational databases. We will conduct rigorous data quality assurance and quality control measures, and standardized longitudinal follow-up of all consented patients with materials in the prostate biospecimen repository. The Core will provide SPORE investigators with expert histopathological evaluation of tumor samples both from patients enrolled on research protocols and from xenograft models. The Core will also provide assistance in performing and interpreting immunohistochemical and in situ hybridization assays, in selecting tissue for microdissection and construction of arrays, and in collaborating with project leaders and the Biostatistics Core. Specific Aim 1. To maintain and expand a model prostate cancer resource to collect, annotate, store, and distribute biospecimens for translational prostate cancer research. Specific Aim 2. To perform systematic pathologic evaluation of all human and animal tissue samples and preparation of appropriate tissues for use by SPORE investigators. Furthermore, the Core aims will serve as a focal point to help combine and prioritize a variety of institutional pathology systems-related development efforts, and we plan to document and publish our findings, standard operating procedures, and best practices, to better serve the research community. Core A will serve RP-2, Core D.